A "hot flush" is a sudden transient sensation ranging from warmth to intense heat and typically accompanied by flushing and perspiration. It is the classic sign of the menopause and the predominant complaint of menopausal women. Epidemiological studies report that the majority of menopausal women experience hot flushes, although with large variation in frequency and intensity (Treatment of the Postmenopausal Woman, Basic and Clinical Aspects, Raven Press 1994, ed. R. A. Lobo).
A positive correlation between plasma levels of calcitonin gene-related peptide (CGRP) and frequency of hot flushes in women has recently been reported (Chen et al., 1993, Lancet (342) 49), in accordance with the potent vasodilatory effect of CGRP (Brain et al., 1985, Nature, (313) 54-56).
Recently, a novel heptadeca peptide, nociceptin, was discovered (Meunier et al., 1995, Nature (377) 532-535, Reinscheid et al., 1995, Science (270) 792-794).
Nociceptin and analogues thereof have been disclosed in WO 97/07212 and in WO 97/07208. These peptides and inhibitors thereof are said to be useful for antagonising physiologic effects of an opioid in an animal, and for treating/preventing a disease related to: hyperalgesia, neuroendocrine secretion, stress, locomotor activity, anxiety, instinctive behaviour, decreasing of learning, memory, curiosity, attention and/or sensory perception.